Panel control key



Feb. 15, 1.955

A. BROWN ETAL PANEL CONTROL KEY 4 Sheets-Sheet l 2 5 9 1 om b. e F d e l .1 F

Feb. 15, 1955 A. BROWN ET AL PANEL coNTRoL KEY Filed Feb. 8, 19.52 Y

4 Sheets-Sheet 2 vInventor A. B R'O WN T. AB E NN E R Attorney Feb 15, 1955 A. BROWN ETAL t e e h Q S t e e h s d. m L o R T N O C m A P 2 5 9 l 8. b. e F d e l .1 nu..

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Inventor A. B RowN- TA-BENN E R n j. A ltorney 4 Sheets-Sheet 4 Inventor A. B ROWN T. A. B E NN E R BMM/ Attorney Feb. l5, 1955 A. BROWN ETAL PANEL CONTRL KEY Filed Feb. 8, 1952 United States Patent O PANEL CoNTRoL KEY Andrew Brown, London, England, and Theodore Addison Benner, New York, N. Y., assignors to International Standard Electric Corporation, New York, N. Y.

Application February 8, 1952, Serial No. 270,717

Claims priority, application Great Britain February 16, 1951 6 Claims. (Cl. 200-4) One feature of the present invention comprises in a railway signalling and points control systems an electric control key which comprises a movable switch member, means for setting said switch member to and locking it in any one of a plurality of switch positions, electrical circuit means associated with each said switch position which when the switch member is set to that position prepares the system to set up a route, and non-locking switch means associated with said key which when operated after said setting causes the desired route to be set if circuit conditions permit.

A further feature of the present invention comprises in a railway signalling and points control system the combination of an electrical control key which comprises a movable switch member which can be set to and locked in any one of a plurality ot distinct switch positions, a contact spring set in each of said switch positions which is operated when the switch member has been set to that position, a common contact spring set and non-locking means for operating said common contact spring set after said movable switch member has been set to any one of said switch positions.

A further feature of the present invention comprises in a railway signalling and points control system the combination of an electrical control key which comprises a movable switch member whose movement occurs in three stages, the iirst stage being rotary movement to any one of a number (including one) of distinct positions, the second stage being axial movement from any one of said positions and the third stage being further axial movement subsequent to said second stage, means for locking the switch member after said second stage of movement, means for restoring the switch member to the position reached as a result of the rst and second stages of movement when it is released after having been mover through said third stage, whereby the third stage of movement is non-locking, a contact spring set associated with each distinct position of the switch member, means responsive to the second stage of movement to operate the appropriate contact spring set, a common contact spring set and means responsive to said third stage of movement to operate the common contact spring set.

A still further feature of the present invention comprises in a railway signalling and points control system the combination of an electrical control key which comprises a movable switch member whose movement occurs in two stages, the first stage being rotary movement to any one of' a number (including one) of distinct positions and the second stage being axial movement from any one of said positions, means for locking the switch member after said second stage of movement, a non-locking push rod mounted concentrically with said switch member, a contact spring set associated with each distinct position of the switch member, means responsive to said second stage of movement to operate the appropriate contact spring set, and a common contact spring set which is operated by pushing said push rod, the push rod being restored to its non-operated position on release by the springiness of the contact or con- 80 tacts of the common contact sprlngset on whlch 1t acts. 4, axial positlon ofthe switch (see Fig. 3), the innermost ice In the specification and claims a movable member is said to be locked when it remains in the position to which it has been manually moved when the operator takes his hand otf the member. To move a member from a locked position it is necessary to perform a positive action to release or restore it. The term includes the holding of a member in set position by friction by relatively-movable parts. Hence non-locking movement is movement such that when the operator takes his hand off the member which has been moved, itim'- mediately returns to its pre-movement position. Different stages of movement of the same member can be non-locking and locking respectively.

The vinvention will now be described with reference to the accompanying drawings, in which:

Fig. l is a part-sectional side elevation of a switch according to the present invention mounted in a panel, being sectioned along the line I-I of Fig. 2.

Fig. 2 is an end elevation of the switch ot' Fig. 1 with its control knob and indicating pointer removed, looking in the direction of the arrows X-X in Fig. l.

Fig. 3 is a view similar to Fig. l of the switch in its locked operated position.

Fig. 4 is a typical circuit employing a switch according to the present invention.

Fig. 5 is a View similar to Fig. l of a second embodiment of the present invention.

Referring now to Figs. l to 3, 1 is a switch knob of insulating material mounted on a hollow metal shaft 2 journalled in bearings 3 and 4. These bearings form part of the die cast framework 5 of the switch, which framework may be of, say, a die cast zinc alloy. The switch is xed to a panel 6 by screws such as 7 which pass through recesses in the panel and are screwed into tapped holes in the switch framework.

A dial 8 bearing indications of a number of switch positions is mounted in front of the panel. In the embodiment described there are twelve possible switch positions, but any suitable number of switch positions may be provided.

A metal collar 9 is mounted axially loose on the shaft 2 between the bearing 3 and knob 1, and carries a pointer 10 which is fixed thereto by screws such vas 11. This collar is arranged to rotate with the shaft and to remain in the angular position to which it is rotated when the switch knob is moved toward or away from the panel.

' To do this the shaft 2 has a narrow longitudinal slot upper surface of the bracket 13 (not shown) which cooperates with a rigid pin (not shown) on the collar 9 as a spline. Collar 9 is provided with an inner shoulder 9a which cooperates with the rear surface 6a ol panel 6. This arrangement ensures that the collar 9 and pointer 10 rotate with the knob 1, but do not move axially if the knob is pushed or pulled. This pin and slot arrangement also allows the pointer to remain close to the dial, so that errors due to parallax when glancing at the switch are reduced.

Mounted on the shaft 2 by screws such as 12 is a single bracket 13.

ln each position to which the switch can be set there is a contact spring pile-up, of which only one, 14, is fully shown. This pile-up consists of one pair of make springs and one pair of break springs. Obviously, any convenient number and arrangement of contact springs can be provided in each switch position. The pile-up 14 is secured to the framework 5 by screws 15, which are insulated from the Contact springs. At the bottom of each pile-up there is a spring member 16 carrying a metal plunger 17 which passes through an aperture 18 in the casing 5.

When the pointer 10 is opposite a switch position and the knob is pushed toward the panel, the inclined engages the plunger 17 in that switch position and pushes it through the aperture 18. In the pile up shown, the contact springs 19 and 20 are connected to but electrically insulated from the plunger 17, which passes through a hole in the contact spring 21. Outward movement of the plunger 17 opens the springs 20 and 21 and closes springs 19 and 22. Thus a single axial movement'of the shaft has controlled all springs in the pile-up. In the new end of the plunger 17 rests in a shallow depression 23 on the tail of the bracket 13. This is the condition illustrated in Fig. 3.

As has been indicated, if the switch knob is released, the switch will be retained or locked in the position to which it has been set, which is shown in Fig. 3. This does not permit the selected operation to be performed. For the operator to cause the required operation it is necessary to push the knob through an extra, or over drive, distance. When this is doneV a stud 24 mounted on the end of shaft 2 closes a pair of overdrive contacts 25. This extra, or overdrive movement is said to be non-locking movement.

Fig. 4 shows a` sample circuit employing overdrive contacts 25. The coil SSC controls the energisation of the required operation, in the present case a sequence switch in a railway signal and points control system. The control contacts rk'l. which are normally open, correspond to the contacts 19` and 22, which are closed when the switch shaft 2 is pushed inwardly. These are in series with two contacts a and b, either of which will be open if for any reason the required sequence switch is not available. lf the sequence switch is available when the overdrive contacts are closed, relay RL operates and via its contact r11 SSC is energised and closes a contact sscl, which bridges the contact r11. The control is` then independent of the overdrive contacts. However, if the sequence switch is not available for use, when the operator releases the knob it returns through the overdrive distance as described below, and contacts 25 open to release RL. This at r11 breaks the SSC circuit. Thus the sequence switch cannot be seized without the operator performing some positive action. If desired, relay RL could be dispensed with, the contacts ril being replaced by the overdrive contacts 25. However, by using a light current relay such as RL, as in Fig. 4, the relatively heavy current used to operate SSC is kept from passing through the overdrive contacts.

The invention can be applied to various known railway signalling and points control systems, such as that of our British Patent No. 520,580. ln this system (see the drawing thereof) a normally open overdrive contact would be inserted in the IR circuit in seriesl with cam L of sequence switch 1, which is only made when the switch is at home. When IR energises its contact then bridges these two contacts.

Reverting to Figs. l and 3, it will be seen` that when the switch has been pushed through its overdrive distance, i. e., the nonlocking part of its movement, the plunger 17 is on the right hand slope of the recess 23; When the knob is released, the pressure of the contact springs and strip 16 on plunger 17 causes a force to be exerted on the bracket 13 via the slope of recess 23. This force tends to drive the shaft 2 towards the position in which it stands in Fig. 3. This force is aided by the resilience of the innermost contact spring at the overdrive contacts 2S, which acts on the stud 24 to return the shaft 2v to the position shown in Fig. 3. Thus the shaft is automatically returned by spring action from the overdrive position to the normal'plunged or pushed position.

Spaced around the inner periphery of the casing there are a number of curved grooves 26 and curved projections 27. Slidablyv mounted through aperture 28a near one end of the bracket 13, there is a stud 28 whose head is substantially the same shape as the curved grooves 26. When the switch is rotated the head of the stud 28 travels over the curved inside of the casing. At each position to which the switch canbc set the stud is aligned with a curved groove. When the switch is pushed thc stud rides along the groove. During the rotary position of its travel the stud 23 is urged inwardly through-thc bracket against the tension of one end 29a of a spring 29, and rides over the projections 27. The other end 29h of spring 29 is anchored to bracket 13. This gives the switch a detect action. so that it cannot have stable equilibrium impositions between adjacent switch positions. if the knob is released before the spring 29`is lully compressed by the stud 28, the tension in the spring forces the stud outward and the switch returns to its original position. Similarly if tbe knob is released after the stud has reached beyond the peak of a projectionthe spring tension forces the switch shaft to the next adjacent angular position.

Behind each curved projection 27 there isa lug 30to prevent axial movement of the switch shaft in intermediate positions. If the switch knob is held in an intermediate position and is pushed, only a slight movement can occur before the rear end 13a of the bracket 13 abuts against the lug 30, thereby preventing any further inward movement of the knob. As has been stated, when the shaft has been rotated to a correct switching position the stud 28 rides along a groove 26, which groove is intermediate adjacent lugs 3i) when the contacts in the pile-up 14 are operated as described above. The lugs 30 form the side Walls of the grooves 26 and serve to prevent any rotary movement of the switch in its plunged position. Thus to cause the switch to assume a' new position it is necessary to pull it back and then turn it.

Although the switch of Figs. l to 3 operates one set of contacts in each position, it is possible as shown in Fig. 2 to arrange for it to simultaneously operate two sets of contacts, e. g. at 14 and 14 respectively (assuming a l2 position switch). This would require two brackets such as 13 and 153' mounted diametrically opposite on the shaft 2.

Fig. 5 shows a switch generally similar to that of Figs. l to 3, but in which the overdrive contacts are operated by an independent push rod 40 mounted within the shaft 2. At its outer end the rod'fi() has a stud member 41', When the knob 1 is pushed the push rod 40 is carried with it by friction until a stud 42 on its rear end contacts the innermost Contact spring of the request contacts 25. This stops the movement of the push-rod 40. The switch member is then retained or locked in the position to which it has been set by friction between the engaging` parts. In this condition thev end 41 of push rod 4t) will project through an aperture 43 in the knob 1. To effect the operation for which the switch has been set it is necessary to push the push rod, when it closes the required contacts 25. The operation is then as described for the switch of Figs. l to 3: on release of the push rod the springiness of the innermost spring of contacts 25 returns rod 40 through the overdrive or non-locking distance.

The only other difference between the two switches is that the bracket 13 in the Fig; 5^ switch is` shorter as the shaft 2 does not itself participate in the overdrive. The switch is held in its operated position? by frictional forces.

In both forms of the switch described the casing is formed in two parts 44 and 45 for convenience of assembly.

While the principles of the invention have been described above in connection with specific embodiments and particular modifications thereof, it is` to be clearly understood that this description is made only by way of example and not as a limitation on the scope of the invention.

What we claim is: y

l. In a railway signalling and points control system, the combination of an electrical control'key which comprises a rotatably and axially movable' switch member, means for locking said switch member in any one of a plurality of distinct rotary switch positions,` a contact spring set in each of said rotary switch positions, means on said switch member for operating the corresponding spring contact set upon the movement of. said` member a predetermined distance axially whensaid' switch member has been set to that rotary position, a common contact sprnig set and non-locking means coupledv to said switch member for operating said common contact spring set, said'non-locking means normally out ofcontact with said common contact spring set and v.movable in an axial directionto operatesaid common contact spring set after said switch member has been axially 'moved said predetermined distance.

2. in a railway signalling'and points controlsystem a :ey as claimed in claim l and in whichsaidnon4locking means is carried by said switch member, said operation being effected by a further axial movement of the switch member.

3. In a railway signalling and. points control system a key as claimedin claim l and comprising an axially movable push rod mounted. concentricallywithin the switch member said push rod carrying said. non-locking means and which when pushed operating said common' contact spring set.

4. In a railway signal-lingand points control systerna key as claimed in claim 3' and in" which the Vcontacts of the common contact spring set on which said push rod acts are springy and serve to restore the push rod to its nonoperated position upon ending the pushing pressure.

5. In a railway signalling and points control system the combination of an electrical control key which comprises a movable switch member whose movement occurs in three stages, the iirst stage being rotary movement to any one of a number of distinct positions, the second stage being axial movement from any one of said positions and the third stage being further axial movement subsequent to said second stage, means for locking the switch member after said second stage of movement, means for restoring the switch member from further rotation to the position reached as a result of the irst and second stages of movement when it is released after having been moved through said third stage, whereby the third stage of movement is non-locking, a contact-spring set associated with each distinct position of the switch member, means responsive to the second stage of movement to operate the appropriate Contact spring set, a common contact spring set and means responsive to said third stage of movement to operate the common contact spring set.

6. In a railway signalling and points control system the combination of an electrical control key which comprises a movable switch member whose movement occurs in two stages, the first stage being rotary movement to any one of a number of distinct positions and the second stage being axial movement from any one of said positions, means for locking the switch member from further rotation after said second stage of movement, a non-locking push rod mounted concentrically with said switch member, a contact spring set associated with each distinct position of the switch member, means responsive to said second stage of movement to operate the appropriate contact spring set, and a common contact spring set which is operated by pushing said push rod, the push rod being restored to its non-operated position on release by the sprnginess of the Contact or contacts of the common contact spring set on which it acts.

References Cited in the le of this patent UNITED STATES PATENTS 1,913,992 Mabie June 13, 1933 1,977,707 Weitzer Oct. 23, 1934 2,248,704 Griiths et al July 8, 1941 2,433,920 Mossman Ian. 6, 1948 2,597,823 Rudd May 20, 1952 2,668,200 Glaze -n Feb. 2, 1954 

